I'm not sure where I first came across this drill, but the "Ken Hackathorn 1 2 3 4 5" drill is a fun exercise. I recently found it in my notes and we decided to run it during a recent range trip.
This is a 15 round drill so it's not too ammunition-rich to be run multiple times, but it's long enough to test things like consistent grip, target transitions, and for most folks, reloads.
Set up three USPSA targets, 1 yard apart at 10 yards. At the start signal take the following shots:
One shot at T1
Two shots at T2
Three shots at T3
Four shots at T2
Five shots at T1
The version of the drill I found called for a draw from concealment, with all A-zone shots within 20 seconds or less. We ran it drawing from an open holster. While it sounds short, 20 seconds it a long time to get off 15 shots. I started out running it way too fast before realizing that I was leaving 5-6 seconds to spare. We didn't record times, or score the targets other than noting how many non-A hits there were before pasting for the next shooter.
While I could have loaded enough rounds to shoot the drill without reloading, I loaded either 10 rounds as I would for a USPSA match, or 8 rounds to match my M1911-toting companions. We didn't top off between turns, so a reload from slide lock would come up at random times adding to the stress.
No, none of us ever shot it perfectly in the 5 or so times we did it last week. But it was a lot of fun and a great learning tool. This will be one drill we will undoubtably return to often.